Japan Aerospace Exploration Agency (JAXA) is pursuing the Global Change Observation Mission (GCOM). GCOM will consist of two series of medium size satellites: GCOM-W (Water) and GCOM-C (Climate). The mission will take over the Advanced Earth Observing Satellite-II (ADEOS-II) and develop into the long-term observation. The Advanced Microwave Scanning Radiometer-2 (AMSR2) for the GCOM-W1satellite, which is the first satellite of GCOM, is now under development. The second satellite of GCOM will be GCOM-C1, which will carry the Second-generation Global Imager (SGLI). AMSR2 is being developed based on the experience of the AMSR for the EOS (AMSR-E), which is currently in operation on the EOS Aqua satellite. The instrument is a dual-polarized total power microwave radiometer system with six frequency bands ranging from 7GHz to 89GHz. Major changes in performance from AMSR-E include the larger antenna diameter of 2.0m for better spatial resolution, additional 7.3GHz channels for mitigating radio-frequency interference, and improvements of calibration system. The GCOM-W1 satellite system is now in Phase-C. We expect a long-term continuity by leading the AMSR2 to the current AMSR-E observation that has been accumulating six years of data records. Current target launch year of GCOM-W1 is the beginning of 2012. Although an important science requirement for GCOM-W1 was to install a microwave scatterometer together with the radiometer for observing various oceanic and weather phenomena, it was not the case for the GCOM-W1 satellite. JAXA and Japanese science community began discussing science requirements for GCOM-W2, the second generation of GCOM-W series. Installing a scatterometer again an important requirement for GCOM-W2. Many synergy effects are expected covering not only instrument-level advantages but also scientific-level merits. At the meeting, we will present the status of the GCOM program and our expectation for installing a microwave scatterometer on GCOM-W2.